A picture of Poison Oak in bud, growing on a cedar tree.
Dwight Smith
Poison Oak on a Cedar Tree
Like poison ivy, poison oak usually grows in clusters of three leaves.
Poison Oak on a Cedar Tree
Poison Ivy Pictures
From Vincent Iannelli, M.D., About.com
Updated: April 13, 2007
About.com Health's Disease and Condition content is reviewed by Kate Grossman, MD
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